// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef BASE_ALLOCATOR_ALLOCATOR_EXTENSION_H_
#define BASE_ALLOCATOR_ALLOCATOR_EXTENSION_H_

#include <stddef.h> // for size_t

#include "base/base_export.h"
#include "build/build_config.h"

namespace base {
namespace allocator {

    // Callback types for alloc and free.
    using AllocHookFunc = void (*)(const void*, size_t);
    using FreeHookFunc = void (*)(const void*);

    // Request that the allocator release any free memory it knows about to the
    // system.
    BASE_EXPORT void ReleaseFreeMemory();

    // Get the named property's |value|. Returns true if the property is known.
    // Returns false if the property is not a valid property name for the current
    // allocator implementation.
    // |name| or |value| cannot be NULL
    BASE_EXPORT bool GetNumericProperty(const char* name, size_t* value);

    BASE_EXPORT bool IsHeapProfilerRunning();

    // Register callbacks for alloc and free. Can only store one callback at a time
    // for each of alloc and free.
    BASE_EXPORT void SetHooks(AllocHookFunc alloc_hook, FreeHookFunc free_hook);

    // Attempts to unwind the call stack from the current location where this
    // function is being called from. Must be called from a hook function registered
    // by calling SetSingle{Alloc,Free}Hook, directly or indirectly.
    //
    // Arguments:
    //   stack:          pointer to a pre-allocated array of void*'s.
    //   max_stack_size: indicates the size of the array in |stack|.
    //
    // Returns the number of call stack frames stored in |stack|, or 0 if no call
    // stack information is available.
    BASE_EXPORT int GetCallStack(void** stack, int max_stack_size);

} // namespace allocator
} // namespace base

#endif // BASE_ALLOCATOR_ALLOCATOR_EXTENSION_H_
